Add a Winget Releaser workflow (microsoft#14965)

[The winget-releaser action] automatically generates manifests for the
[Winget Community Repository] and submits them.

I suggest adding Dependabot to keep the action up to date. There were
many cases where the action was failing due to an outdated version.

Closes microsoft#14795

[The winget-releaser action]:
https://github.com/vedantmgoyal2009/winget-releaser
[Winget Community Repository]: https://github.com/microsoft/winget-pkgs

.github/workflows/winget.yml

@@ -0,0 +1,27 @@
+name: Publish to Winget
+
+on:
+  release:
+    types: [published]
+
+env:
+  REGEX: 'Microsoft\.WindowsTerminal(?:Preview)?_Win10_([\d.]+)_8wekyb3d8bbwe\.msixbundle$'
+
+jobs:
+  publish:
+    runs-on: windows-latest # Action can only run on Windows
+    steps:
+      - name: Extract version from release asset
+        id: extract-version
+        run: |
+          $version = '${{ toJSON(github.event.release.assets.*.name) }}' | ConvertFrom-Json | Select-String -Pattern $env:REGEX | ForEach-Object { $_.Matches.Groups[1].Value }
+          Write-Output "version=$version" >> $env:GITHUB_OUTPUT
+
+      - name: Publish ${{ github.event.release.prerelease && 'Preview' || 'Stable' }}
+        uses: vedantmgoyal2009/winget-releaser@v2
+        with:
+          identifier: Microsoft.WindowsTerminal${{ github.event.release.prerelease && '.Preview' || '' }}
+          version: ${{ steps.extract-version.outputs.version }}
+          installers-regex: ${{ env.REGEX }}
+          token: ${{ secrets.WINGET_TOKEN }}
+          fork-user: DHowett